Hardware Review: Kensington Expert Mouse Wireless

Is your mouse giving you grief from too many hours spent pointing, clicking, and dragging your way across a desktop? If you’re a mental health practitioner working extensively with clients online, you probably cannot avoid the pointing, clicking, or dragging — but you can avoid the mouse. Just turn it upside down, cut off the cord, and call it a trackball instead. Or, like Kensington, call it the Expert Mouse Wireless.

Mice, Trackballs and Repetitive Stress Injuries

As I mentioned at the beginning of our review of the Kinesis Advantage USB ergonomic keyboard, spending a great deal of time in front of a computer as a mental health practitioner working with clients online can be a great way to discover the fun of repetitive stress injuries.

Keyboards can be bad enough, but what about mice? You reach out a hand, grasp the mouse, and then move at least your wrist, if not your entire forearm and sometimes even upper arm and shoulder, in order to move a tiny little pointer on a computer display. When moving across your computer’s virtual desktop, your hand is moving across your real desktop, over and over, every day. Even the most adroit ‘power users’, who prefer speedy keyboard shortcuts to the comparatively slow physical movements of the mouse, really cannot avoid the arm-waving routine all the time.

OK, I admit it: I don’t like mice very much. As someone who has experienced repetitive strain, I’m convinced there’s a better way.

Kensington Expert Mouse Wireless

That’s where the Kensington Expert Mouse Wireless comes in.

Despite the name, the Expert Mouse isn’t a mouse at all, but a trackball. Functionally, it is like an old-fashioned mouse with a ball inside, but turned upside down: instead of moving the ball by moving the mouse across the desktop, you move the ball with your fingertips.

Kensington Expert Mouse Wireless

Expert Mouse Wireless

(I say ‘old fashioned’ because these days, most mice don’t use a ball and instead track movements by bouncing a beam of light directly off your desktop; the Kensington Expert Mouse also uses optical tracking, but to track the ball.)

For users who have never tried a trackball before, I would imagine the distinctly different pointing action probably takes some getting used to; I know of many people who say they don’t like trackballs in the least. However, if you have ever experienced discomfort as a result of moving your whole arm around with a mouse attached, I believe the basic idea of a trackball — whether from Kensington or a competing supplier — is well worth considering. There’s a reason why trackballs are so common in medical imaging and other fields which require extensive precise movements of a pointing device…

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Kensington Expert Mouse Features and Software

The ergonomic benefits of the Kensington Expert Mouse Wireless don’t stop with the fact it’s a trackball. The dark circle which surrounds the Expert Mouse’s ball is actually a unique scroll wheel in the form of a ring. When I first saw the scroll ring in a photo, I imagined myself having to move it with thumb and forefinger, but in fact it is easy to spin with whatever single finger suits your hand position; usually, I use my ring finger.

The device also features four buttons, all of which can be programmed with the included MouseWorks software, and both the top two and the bottom two can be pressed simultaneously (‘chorded’) for additional functions, making a total of six. Depending on your work habits, these additional buttons can be configured to type keystrokes, open URLs, launch applications, open files, and more; some example settings are shown in the Mac OS X version of the MouseWorks configuration screen below.

Kensington MouseWorks configuration software.

MouseWorks button configuration

The MouseWorks software also provides extensive customization options for scrolling, click speed, and ball tracking — the last of which can be customized in great detail, enabling you to set both linear speed and acceleration curves for both slower and faster movements.

MouseWorks accleration settings.

MouseWorks acceleration configuration

I found it rather fiddly to get the settings just right on the configuration screen above: the settings cover an extremely wide range of speed and acceleration, of which I found only a very tiny range to be useful for my own way of using the device. I would have preferred finer control over a smaller range of settings, rather than coarser control over a huge range of settings. (Oddly, I don’t remember ever experiencing this before with Kensington trackballs, which I first tried in the early 1990s.)

The whole device is of course wireless, communicating with a base station plugged into a USB or PS/2 port — so you can forget about wrestling with a cord when you want to re-position it. The trackball is powered by two C cells, and the Expert Mouse Wireless comes with two high quality alkaline cells with a claimed life of 2-6 months of normal use. After 2 months of use several hours per day, our cells were still going strong. We tried NiMH rechargeable cells, with mixed results: although the device operates just fine with them, with no discernible differences in performance compared to alkalines, the rechargeables give very little life on a charge, expiring after less than one week of use. I imagine this is due to the lower voltage of NiMH cells (1.2v as compared to 1.5v for alkalines): perhaps the threshold voltage for the device to function is just fractionally lower than 1.2v.

Last but not least, the Expert Mouse Wireless comes with a detachable wrist rest that takes some of the pressure off the contact point between your wrist and desk. I personally found the rest just right for achieving the straight wrist angle that is recommended to minimize strain, but another reviewer who tried the device found that she preferred something a little higher to get the same effect.

Usability and Build Quality

Overall, the Expert Mouse Wireless is a pleasure to use.

The many buttons reduce trips back and forth between keyboard and trackball and can speed up otherwise relatively slow tasks. Being right-handed, I find the top left button impossible to use without shifting my hand position, but the other three require no change in position at all.

The integrated scroll ring, although it feels rather clunky and flimsy in comparison to the rest of the device, is very well thought-out and is instantly available without requiring a shift in finger position. The scrolling axis (left-right versus up-down) can be changed with an assigned button click, or another click can set the ball itself to do the scrolling — a function which is particularly useful for dealing with large images or other workspaces requiring both horizontal and vertical scrolling.

This brings us to the ball itself. We actually wound up testing two different devices, for a reason I’ll explain in a moment, and we noticed a very significant difference between the smoothness of the rolling action. The first device began rather rough, as if the three point bearings which support the ball in the housing needed some time to wear. I found myself frequently stopping work to roll the ball around vigorously, in hopes of helping the rolling action to settle in. After several weeks of use, the action did become much smoother.

Our second unit, however, was noticeably smoother than this, even brand new, straight out of the box. Immediately, I found that the smooth rolling enabled me to use the inertia of the ball to get my pointer from one side of my 20-inch widescreen display to the other: an initial flick starts the ball rolling, and light finger pressure ‘catches’ it again when the pointer has moved to the desired ‘landing spot’ on the other side of the screen.

So why did we review two separate devices? We had noticed with the first trackball that when left idle for a few seconds — say, long enough to read a web page — the Expert Mouse Wireless would stop responding very briefly. While there was just a latency in its response to ball movements — perhaps half a second to a second before it started working normally again — the scroll ring would not respond at all. Once the ball was rolled around again for a moment, however, both ball and scroll ring returned to their normal quick response. I contacted Kensington, who indicated that this was not at all normal behaviour, and they sent a second device.

However, in terms of the response latency, the behaviour we found was identical: both devices show the same ‘lag’, as if they might be going into a temporary sleep after a few seconds of idle time. A second reviewer gave the Expert Mouse Wireless a thorough workout on a Windows machine, and the results in this respect were the same as on my Mac OS X machine. So, on the face of it, it looks like it cannot be due to an isolated software problem. Yet, having tried two devices, it doesn’t seem likely to be an isolated hardware fault. I can only speculate as to whether there might be some conflict with another wireless device in our vicinity (telephone, keyboard, wireless network, alien mothership) that might be causing the latency. Or, perhaps we are both just picky, and we notice a latency that Kensington’s testers do not?

Overall Assessment

Both reviewers agree that, despite the problem of ‘napping’ during a few seconds of idle time, the Kensington Expert Mouse Wireless is a real winner. For users who like the general idea of a trackball, the design of the Kensington device offers a whole host of usability and ergonomic features that make it one of the best available.

The company has been making trackballs for 15 years, and this latest refinement to their product line suggests they’re doing it pretty well. Kensington stands by the device with a 5-year warranty and free technical support.

System Requirements and Pricing

You can read more about the Expert Mouse Wireless and other pointing devices at the Kensington site. Most of their devices are fully compatible with both Macs and Windows PCs. The Expert Mouse Wireless requires:

  • PC running Windows 98 or later with an available USB or PS2 port
  • Mac running OS X with an available USB port
  • An internet connection or CD ROM drive is required to install the MouseWorks software

The Expert Mouse Wireless retails for US$119.99. A non-wireless version is available for US$20 less, at US$99.99.

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